A physical uplink control channel (PUCCH, Physical Uplink Control Channel) of a long term evolution technology (LTE, Long Term Evolution) uses a code division multiple access (CDMA, Code Division Multiple Access) technology. Because the CDMA technology is a self-interference system, when co-channel interference reaches a certain degree, a success rate of demodulating information carried by the PUCCH may be affected. Increasing PUCCH transmit power of a user terminal (UE, User Equipment) is a method for increasing the success rate of PUCCH demodulation.
For example, the PUCCH transmit power of the UE at a subframe (Subframe) i is indicated by PPUCCH(i), where PPUCCH(i)=min{PCMAX, P0—PUCCH+PL+h(nCQI, nHARQ)+ΔF—PUCCH(F)+g(i)}. The PCMAX is maximum transmit power of the UE. The P0—PUCCH is a received power level expected by a base station, and P0—PUCCH=P0—NOMINAL—PUCCH+P0—UE—PUCCH, where the P0—NOMINAL—PUCCH indicates a cell-specific received power level of the PUCCH expected by the base station, and the P0—UE—PUCCH is a power offset value relative to the P0—NOMINAL—PUCCH. The PL is a downlink path loss value estimated by the UE. The h(nCQI, nHARQ) is a value decided by a PUCCH format, where nCQI is the number of information bits of a channel quality indicator (channel quality indicator, CQI), and nHARQ is the number of information bits of an HARQ. The ΔF—PUCCH(F) is a power offset value of a different PUCCH transmission format relative to a reference format (DCI FORMAT 1A). The g(i) is a calibration value of inner loop power control, and is used to compensate an error which is set for initial power of open loop power control, and
            g      ⁡              (        i        )              =                  g        ⁡                  (                      i            -            1                    )                    +                        ∑                      m            =            0                                M            -            1                          ⁢                              δ            PUCCH                    ⁡                      (                          i              -                              k                m                                      )                                ,where the δPUCCH is a transmit power control command (Transmit Power Control command, TPC command) on a subframe.
In the prior art, after receiving the P0—NOMINAL—PUCCH, P0—UE—PUCCH, and δPUCCH, the UE may calculate the PUCCH transmit power at the subframe i by using the foregoing formula, but the PUCCH transmit power at the subframe i calculated by the UE is inaccurate, and thus an effect of suppressing network interference caused by increasing the PUCCH transmit power is not good.